From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:54739) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VTXdW-0007Dl-3b for qemu-devel@nongnu.org; Tue, 08 Oct 2013 09:47:49 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VTXdO-00005G-Og for qemu-devel@nongnu.org; Tue, 08 Oct 2013 09:47:42 -0400 Received: from cantor2.suse.de ([195.135.220.15]:34807 helo=mx2.suse.de) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VTXdO-0008W9-JK for qemu-devel@nongnu.org; Tue, 08 Oct 2013 09:47:34 -0400 Message-ID: <52540CEF.2030507@suse.de> Date: Tue, 08 Oct 2013 15:47:27 +0200 From: =?ISO-8859-15?Q?Andreas_F=E4rber?= MIME-Version: 1.0 References: <1381222058-16701-1-git-send-email-pbonzini@redhat.com> In-Reply-To: <1381222058-16701-1-git-send-email-pbonzini@redhat.com> Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH 0/8] Make icount thread-safe List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini Cc: qemu-devel@nongnu.org, alex@alex.org.uk Am 08.10.2013 10:47, schrieb Paolo Bonzini: > This series moves the icount state under the same seqlock as the "norma= l" > vm_clock implementation. >=20 > It is not yet 100% thread-safe, because the CPU list should be moved > under RCU protection (due to the call to !all_cpu_threads_idle() > in qemu_clock_warp). However it is a substantial step forward, the > only uncovered case being CPU hotplug. >=20 > Please review. >=20 > Paolo >=20 > Paolo Bonzini (8): > timers: extract timer_mod_ns_locked and timerlist_rearm > timers: add timer_mod_anticipate and timer_mod_anticipate_ns > timers: use cpu_get_icount() directly > timers: reorganize icount_warp_rt > timers: prepare the code for future races in calling qemu_clock_warp > timers: introduce cpu_get_clock_locked > timers: document (future) locking rules for icount > timers: make icount thread-safe These patches touch cpus.c exclusively, so "timers:" is rather misleading= . As you know I have pending patches (in need of rebase due to the performance issue you raised) moving the icount CPU fields around. Is there anything in particular I should be aware of? Looks to me as if this may be orthogonal? What about the previous patch disabling icount for -smp? Does this series supersede it or does it fix different concurrency issues? Thanks, Andreas > cpus.c | 110 ++++++++++++++++++++++++++++++++++++-----= -------- > include/qemu/timer.h | 26 +++++++++ > qemu-timer.c | 74 +++++++++++++++++++------ > 4 files changed, 163 insertions(+), 47 deletions(-) > create mode 100644 include/qemu/seqlock.h --=20 SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 N=FCrnberg, Germany GF: Jeff Hawn, Jennifer Guild, Felix Imend=F6rffer; HRB 16746 AG N=FCrnbe= rg